Priming device

ABSTRACT

A priming device inside of a chamber includes a flat ring, in which is disposed a shallow cup that is encircled by an integral flange overlapping one side of the ring, to which one side of the flange is secured. The bottom of the cup has a hole through it and the cup contains pyrotechnic material. The opposite side of the flange is secured to a thin metal wall of the chamber. The material in the cup is detonated by striking the thin wall to bend it into the cup so that it will press against the pyrotechnic material.

Unite States fie t [151 3,665,859 Caples 1 30, 1972 541 PRIMING DEVICE733,638 5/1903 Gardner.... l02/86.5 [72] lnvemor: Allen s. Capks,Baltimore, M d 3,124,075 3/1964 Eldh et a] 102/865 [73] Assignee:Catalyst Research Corporation, Baltimore, Primary Examiner-Samuel W.Engle M Attorney-Brown, Murray, Flick & Peckham 22 F'] d: Ma 25 1970 l 1y 57 ABSTRACT 21 A 1. No.: 40 156 1 pp A priming device inside of achamber includes a flat ring, in which is disposed a shallow cup that isencircled by an integral [52] US. Cl. l02/45, 102/70 R, 102/865 flangeoverlapping one Side f h ring m which one side f [5 l] Int. Cl. ..F42C19/10 the flange is Secured The bottom of the cup has a h [58] Field ofSearch 102/46 45 through it and the cup contains pyrotechnic material.The opposite side of the flange is secured to a thin metal wall of the[56] References Cned chamber. The material in the cup is detonated bystriking the UNITED STATES PATENTS thin wall to bend it into the cup sothat it will press against the pyrotechnic material. 1,313,801 8/1919Doran ..102/86.5 3,186,341 6/1965 Bjorklund ..l02/86.5 4 Claims, 2Drawing Figures Patented May 30, 1972 lNVE/VTOR. ALLEN 5. 01, 4 5

Fig.2

PRIMING DEVICE It is an object of this invention to provide a primingdevice that can have a much smaller volume than priming devices usuallyused for firing pyrotechnic compositions in a chamber. Other objects areto provide a priming device that is completely enclosed and sealed,which does not have to be struck in an exact spot in order to detonateit, which is much simpler than conventional primers with their holders,and which has fewer parts and requires no particular care or skill inmounting it in position.

The preferred embodiment of the invention is illustrated in theaccompanying drawings, in which FIG. 1 is an end view, partly brokenaway, of a chamber containing the priming device; and

FIG. 2 is a fragmentary view, partly in section on the line "-11 of FIG.1.

Referring to the drawings, a sealed chamber 1 containing a pyrotechniccomposition 2 that is to be fired has a relatively thin metal wall. Thismay be an outside wall of the chamber or an inside partition wall. Inthe drawing, it is shown as being the end wall 3 of the chamber that isin the form of a can. Inside the chamber or can there is a primingdevice that is surrounded by composition 2. The principal portion of thedevice is a shallow cup 4 encircled by a flat integral radial flange 5.The cup fits in a flat ring 6, like a washer, with the flangeoverlapping one side of the ring and secured to it by an adhesive or byspot welds 7 or the like. The opposite side of the flange is secured inthe same or similar manner, such as by an adhesive 8, to the innersurface of the thin metal wall of the can. This wall therefore closesthe cup. The cup contains an impact sensitive pyrotechnic material 9 ofany well known type, which preferably is in the form of a coating on thebottom of the cup. It is spaced from the thin end wall of the can. Thebottom of the cup is provided with a central hole 10 through it.

When the thin wall of the can is struck by an instrument that will causeit to be bent into the cup and strike the pyrotechnic material 9therein, the latter will be detonated and the fire will pass throughhole 10 in the cup to fire the pyrotechnic composition 2 in the canaround the priming device.

The washer or ring 6 adds rigidity to the device for handling and itprotects the cup from compressive forces due to the pyrotechnic material2 consolidated or pressed tightly against the outside of the devicewithin the can. This ring, along with the space between the can wall andthe pyrotechnic coating in the cup, isolates the coating from prematureor inadvertent firing.

It will be seen that this priming device is very simple and requires butlittle space. It has only two parts and requires no particular care orskill to mount it in place. The entire device is sealed inside the canso that it cannot be affected by the out side atmosphere. Because thepyrotechnic coating within the cup is spread over a relatively largearea, a strike against it by the wall of the can anywhere within thatarea will fire the primer, unlike conventional primers which require astrike very nearly in the exact center. If a conventional primer holderis mounted on a thin wall, the relatively large diameter of the holdertends to diffuse part of the striking force into elastic deflection ofthe wall in a direction and manner detrimental to firing the primer. Onthe other hand, with the arrangement disclosed herein, the appliedstress is concentrated in the small firing pin area so that more plasticthan elastic deformation occurs.

According to the provisions of the patent statutes, I have explained theprinciple of my invention and have illustrated and described what I nowconsider to represent its best embodiment. However, I desire to have itunderstood that, within the scope of the appended claims, the inventionmay be practiced otherwise than as specifically illustrated anddescribed.

I claim:

1. In combination with a thin metal wall of a chamber, a priming devicein the chamber comprising a flat ring, a shallow cup disposed in saidring and encircled by an integral flange overlapping one side of thering, means securing the ring to the adioining side of said flange, thebottom of the cup having a ho e through it, a coating of impactsensitive pyrotechnic material on the inner surface of the bottom of thecup, and means securing the opposite side of said flange to said wall toclose the cup, said wall being deformable into the cup against saidmaterial to detonate it.

2. In the combination recited in claim 1, said chamber being sealed andfilled with a pyrotechnic composition to be fired by said primingdevice.

3. In the combination recited in claim 1, the combined thickness of thering and flange being at least as great as the height of the cup.

4. In the combination recited in claim I, said first-mentioned securingmeans being disposed between said ring and flange, and saidlast-mentioned securing means being disposed between said flange andwall.

1. In combination with a thin metal wall of a chamber, a priming devicein the chamber comprising a flat ring, a shallow cup disposed in saidring and encircled by an integral flange overlapping one side of thering, means securing the ring to the adjoining side of said flange, thebottom of the cup having a hole through it, a coating of impactsensitive pyrotechnic material on the inner surface of the bottom of thecup, and means securing the opposite side of said flange to said wall toclose the cup, said wall being deformable into the cup against saidmaterial to detonate it.
 2. In the combination recited in claim 1, saidchamber being sealed and filled with a pyrotechnic composition to befired by said priming device.
 3. In the combination recited in claim 1,the combined thickness of the ring and flange being at least as great asthe height of the cup.
 4. In the combination recited in claim 1, saidfirst-mentioned securing means being disposed between said ring andflange, and said last-mentioned securing means being disposed betweensaid flange and wall.